waldo041 wrote:I have noted before that a GGG blaster performs different then an original Blaster circuit.

~waldo

Agreed. Mine goes temporarily insane and tries to blow speakers. Or it could be the gain pot I guess. Both are marked for death. Now to find a vintage Alembic...

On the topic at hand, I select buffer or blaster, pre-OBEL, via a DPDT switch, as I don't want an LED on my guitar. Or at least not one that anyone but I can see. When I put my buffer/blaster(Milobender first suggested the either/or setup to me, thanks, man!) guitar together I wasn't concerned with passive operation. Seemed to me that if I wanted a passive signal, then a second, dedicated passive guitar would be the best solution anyway.

TI4-1009 wrote:Don't get me wrong- I like the sound of the blaster as an option, it's just different than the buffer.

I think you have misunderstood what I stated, possibly my grammar. The GGG Blaster clips itself because the FET is not biased correctly. An original Blaster FET is biased correctly and does not clip on it's own with the Alembic circuit. It is more of a clean transparent boost, and when set at the lowest gain is pretty close to a Buffer.

~waldo

Disclaimer: I make and sell Buffers. I also sometimes Modify, Build and sell preamps and amplifiers. My opinions are not intended to be sales pitches. I am a one man shop and prefer to spend time with my wife and family, i work full time on call and love to spend my spare time doing other things. I only make, modify or build things for those that seek them.

C3 cap for power filteringR1 100 vs 68 for RF filteringR6 for the switch pop R4 is the pot for variable gain as opposed to the Alembic 50k fixed resistor

Assuming it's the same transistor, and you build it as a guitar mount- not in pedal form- which of those mess up the biasing?

Second question- since they already have the 1M5 resistor there for pop reduction, I assume I didn't need to add the 1 meg on my build? Is the extra meg changing/hurting anything?

I think- at least on my build- with the pot turned all the way down the GGG and your buffer sound pretty close. The GGG may be a tad "brighter".

(and your grammar was perfect... )

What I should say is that there are differences between JFET's, try a J201 compared to a 2N5457 and you will hear the difference compared to an original e230/j230. The circuit is self biasing, so any of the mentioned jfet's work in the circuit, they just all perform different within the circuit.

~waldo

Disclaimer: I make and sell Buffers. I also sometimes Modify, Build and sell preamps and amplifiers. My opinions are not intended to be sales pitches. I am a one man shop and prefer to spend time with my wife and family, i work full time on call and love to spend my spare time doing other things. I only make, modify or build things for those that seek them.

After a lot of experimenting, I have come to the conclusion that I only like the Blaster in a guitar without the buffer and OBEL. Too much going on and can cause noise when both are engaged at the same time.

IMHO, If you have the OBEL and buffer, you don't need the blaster on top of it.

Don't get me wrong, I love the blaster in a stock strat spliced into the output (as designed). Works great in that situation.

Buffer or blaster (but not both), OBEL or not OBEL- just flip the switch. All four options available.

Yes, I know the options and thanked Waldo for the diagrams. I'm not saying I don't understand that. I'm saying, that after a lot of experimenting utilizing those diagrams etc., I would not have a blaster in a guitar with a OBEL and buffer because it would go unused. To me, IMHO, the buffer with the OBEL (25k volume pot) sounds way better than the blaster. As I said, the blaster does sound great in a stock strat, but if I was going to put a buffer/OBEL in that same strat, I'd ditch the blaster. That's all!

Buffer or blaster (but not both), OBEL or not OBEL- just flip the switch. All four options available.

Yes, I know the options and thanked Waldo for the diagrams. I'm not saying I don't understand that. I'm saying, that after a lot of experimenting utilizing those diagrams etc., I would not have a blaster in a guitar with a OBEL and buffer because it would go unused. To me, IMHO, the buffer with the OBEL (25k volume pot) sounds way better than the blaster. As I said, the blaster does sound great in a stock strat, but if I was going to put a buffer/OBEL in that same strat, I'd ditch the blaster. That's all!

I don't think we're all on the same page about this setup. That switch diagram is how my guitar is wired, simple and very flexible. It's merely providing options, so that the "blaster in a stock strat" option is there, plus the "buffer and OBEL" option. Also included are the "buffer no OBEL", as well as "blaster and OBEL", if you are so inclined. When I was planning my build I was trying to choose an onboard preamp and Milobender asked me if I had considered having both; after that it didn't make sense to me to choose once and be committed when I could choose between them endlessly with a switch.

Buffer or blaster (but not both), OBEL or not OBEL- just flip the switch. All four options available.

Yes, I know the options and thanked Waldo for the diagrams. I'm not saying I don't understand that. I'm saying, that after a lot of experimenting utilizing those diagrams etc., I would not have a blaster in a guitar with a OBEL and buffer because it would go unused. To me, IMHO, the buffer with the OBEL (25k volume pot) sounds way better than the blaster. As I said, the blaster does sound great in a stock strat, but if I was going to put a buffer/OBEL in that same strat, I'd ditch the blaster. That's all!

I don't think we're all on the same page about this setup. That switch diagram is how my guitar is wired, simple and very flexible. It's merely providing options, so that the "blaster in a stock strat" option is there, plus the "buffer and OBEL" option. Also included are the "buffer no OBEL", as well as "blaster and OBEL", if you are so inclined. When I was planning my build I was trying to choose an onboard preamp and Milobender asked me if I had considered having both; after that it didn't make sense to me to choose once and be committed when I could choose between them endlessly with a switch.

The only problem with this is that you still have a 25K volume pot that is not stock to a Strat, so how can you have "blaster in a stock strat" option?

With both the buffer and blaster bypassed, there wouldn't be any difference with the volume pot turned all the way up (zero K), but it will react different when you turn it down (not much travel between full on and full off) because when you take both the pre/buffer and the blaster out of the circuit, it goes from high impedance to low impedance, which (as you probably know) usually uses a 250k or 500k volume pot. That's been my experience, anyway.

I should clarify that I didn't mean that I can't hear the difference between a 250k and a 25k pot, I mean I can't hear much difference between my guitar's setup and it's intended purpose,which is to sound like Alligator(among other things). I know, Alligator isn't a "stock" strat, but it's blaster was post-volume pot and always on, IMO the right way to use it in a stock strat. It seems like Jerry didn't have much use for a low-impedance, passive guitar signal, and only switched guitars when there was a problem with whatever was his main one at the time. Following that logic, a variety of tonal possibilities was my chief design point, and then the general beefing up and improvement of the wiring. Hence the "either-or" setup. At no point after the first DPDT switch is the signal ever passive. Either buffer or blaster, never both, and never bypassed. I guess if I want a passive signal I'll get a stock strat. And shorter cables. I get pretty convincing 70's tones, and even decent 80's (to my ears).

And instead of adding a blaster on board, I use a clean boost pedal. I wish I had two, one always on, and another for oomph. Pedals easier to step on than flipping a switch for me

The problem with this approach is that one of the key reasons for having the buffer on board is so that there is no cable run between pickup and buffer, no cable capacitance to suck tone when setting the guitar at volumes less than 100%. If the buffering is in a pedal, then the guitar suffers some tone loss on the way to that pedal. Waldo has pointed out how SO much of Jerry's playing was done with the guitar set well below clipping, way below 100%. To keep that same clarity at all volumes I don't see any good way around having the buffer in the guitar itself. But in practice, if you use as short a cable run as possible with really good, ultra-low capacitance cable, you can kind of get close, but even still there's nothing like the zero-capacitance sound of having the buffer in the guitar.

And I've found it to be true what Waldo says about the GGG "blaster" circuit using a modern J201 or similar. These JFET's don't bias properly using the original Blaster resistor values and headroom is lost and they can clip more easily from a hot pickup or hard pick attack. It would be better to alter the resistor values to better bias these newer JFET's. I'll try to scope out some better J201 blaster values when I find the time, and I'll share that info here. There is indeed something kind of special about the original Blasters or at least those original JFET's. I've still got two Blasters that I bought in the 80's.